Helical Power Gear Hobbing..Over Centers, Multiple Passes.

[@MattysWorkshop]

Gday Tom, I know I said this before here but I’ll say it again, this machine you’ve built is truly a work of art, I always enjoy watching your adventures mate, beautiful job as always, cheers

[@thomasstover6272]

Glad you’re still watching, Matty! Cheers!

[@Mike40M]

Some 50 years ago I worked teaching students about machine tools. They had to calculate how to set up a hobbing machine for different angled helical gears. The machine used a differential to adjust hob rotation to workpiece rotation. The machine had one set of gears to set for number of teeth and one set for helix angle. When they had done the math they had to make a gear. Fun to watch. If the machine is set up wrong, it starts looking ok but ends up with a smaller diameter blank.

[@thomasstover6272]

Thanks for sharing your memory, Mike. I believe that I must have made every mistake your students made, plus a few of my very own!

[@alexanderkramer6047]

Amazing. I would love to see some more math involved with these gears and some more examples. If anything I think your videos are too short. Can’t get enough!

[@thomasstover6272]

Can do! Thanks for watching…

[@joeg679]

Nice Job Tom, you’re lucky you didn’t break your hob when you gear train came loose. I had that happen to me as well, it broke a few teeth in my hob, I had to do a hob shift. After that before I would start hobbing, I would take two minutes and check all my gears to make sure they were tight and where they should be. Keep up the good work.🙂

[@thomasstover6272]

The VFD tripped and stopped the motor before things got really bad. But, yeah, lucky….

[@fullmetalmachinist3883]

I recently bought FA5U machine with all hobbing attachment and setting up VFD properely is first thing i will do with it. Second is DRO. It comes with 2 dividing heads (regular with knob and powered one) and huge cabinet of gears for the drivetrain. I think it will handle up to module 5.@@thomasstover6272

[@BLECHHAUS]

I love seeing how gears are milled :-)

[@lawmate]

This is such a cool setup! I might be totally wrong on this, but maybe you'd get a stiffer setup if you cut the internal centres on the mandrel shaft a little deeper. It looks like there isn't a large contact surface area between the shaft and support centres, and that will be taking the full load of the cut, so prone to a bit of elastic deformation and chatter. Might not be a problem though. Very jealous of the setup.

[@thomasstover6272]

Thanks for the comment! I’ll try that when I start chasing the chatter.

[@billdoodson4232]

Would really like to see a full workshop tour Tom.

[@thomasstover6272]

Coming soon!

[@TalRohan]

ooh those are pretty, I have some of these from one of my landrover gearboxes. I'm not sure why or what I'm going to do with them but I do just like the look of them.

[@ThePottingShedWorkshop]

Those gears turned out really nice. Reassuring to find out its not just me who has mishaps making helical gears!

[@thomasstover6272]

Thanks, Robert! Next time I’ll try 3 passes, but I think they will do…

[@ahmeddrdeer1399]

Nice work nice chanell Go on l like your work

[@perrypark8485]

Always appreciate your content. Cool stuff

[@bulletproofpepper2]

Wow, thanks for sharing, great work.

[@Some_DIY]

Great job! Liked and subscribed.

[@thomasstover6272]

Thank you very much!

[@greglaroche1753]

Very interesting and informative. Thanks. Was the hob cutter all one piece ? Did you buy or make it ? Thanks again. I’m subscribed.

[@thomasstover6272]

The hob is one piece. I believe it’s an “import”. I may try to make a hob someday, but the process is…arduous.

[@ronaldfairhurst2914]

very nice I wish I had your knowledge, make my cincinnati #2 more usable

[@thomasstover6272]

Thanks, but you’ve got the right machine! Have fun!

[@Panzax1]

That's probably the most amazing shop-built thing I have seen on youtube. I wonder about a few things: The load on the table is extremely uneven, in addition to being on the far side of the travel too. Does this introduce any tilt in your arbor ? Maybe you adjusted for that already. Regarding the between-centres machining: Wouldn't it be a more stable setup with a 4-jaw chuck? Slower to set up though.

[@thomasstover6272]

Thanks for the comment! I keep the gibs pretty snug, plus I indicated the arbor level, which should be good enough, since the X axis travel is only about an inch to make a gear. You might be right about the chuck, but then I would have to indicate the chuck end of the arbor each time I mounted it. At large helix angles the size of the chuck is a setup issue, too. …see how it goes, I guess!

[@Panzax1]

@@thomasstover6272 Yes, the 4-jaw has a few drawbacks in that setup. And maybe the between-centres method is rigid enough. I was wondering what sort of steel you are using for your geartrain ? And what sort of hob is that ? I have cut some gears from 4140HT and the HSS gear cutters does not last long..

[@thomasstover6272]

@@Panzax1 Most of the gears I’ve made have been 1018 or 8620. The hobs are usually M2 steel, through-hardened. I’ll have to consider heat-treatable alloy when I get further into power transmission gearing rather than index gears. I run the hob at about 100sfpm with .006 in/rev feedrates, so pretty slow.

[@Panzax1]

@@thomasstover6272 You run a better hob material and softer steel, so it makes sense that it will last longer. Thanks for your answer.

[@kisoia]

Great work Tom, what is the material for the gear? Thanks for the video :)

[@thomasstover6272]

Thanks! Steel, either 1018 or 8620.

[@pawekowalski7469]

👍👍 mam taką tokarkę jak ty 😀

[@markfischer9216]

The first of millions.

[@thomasstover6272]

Well, dozens, surely…

[@jimsvideos7201]

Quite a feat.

[@joell439]

👍👍😎👍👍